Composite materials such as graphite-epoxy, boron-epoxy, etc., are replacing metal in the manufacture of airframes on a rapidly expanding scale. Such materials are, in many respects, superior to metal in corrosion-resistance, durability, strength, and produce substantial reductions in cost and weight.
As an example, in the manufacture of the forward fuselage section of the Northrop YF-17 aircraft, the use of graphite composite materials reduced weight by 40%, and costs by 30% compared to the all-metal design for the same assembly. Moreover, the all-metal fuselage section of the aircraft required 1300 parts and 20 subassemblies, whereas only 260 parts and 10 subassemblies were required in an identical section fabricated of composite materials.